Band-tightener for concrete-forms.



(J. M. MARKHAM. BAND TIGHTENER FOR GONGBETE FORMS. APPLICATION FILED NOV. 30, 1908.

918,568. Patented A 1- .20,1909.

rus'mmms Psrsrs m, WASHINGTON. n c

CHARLES M. MARKI-IAM, OF CHICAGO, ILLINOIS.

BAND-TIG-I-ITENER FOB CONCRETE-FORMS.

Specification of Letters Patent.

Patented April 20, 1909.

Application filed November 30, 1908. Serial No. 465,035.

ments in Band Tighteners for Concrete- Forms, of which the following is a SPGCil'lC-iltion.

My invention relates to forms for concrete construction and more particularly to improvements in tools employed in the ap plying of adjustable bonds to such forms.

The object of my invention is to provide a device of the character mentioned adapted to be readily and efl'ectually used in connection with adjustable bonds of a certain con struction in binding or tightening of the same around a segment of a form.

A. further object 01' my invention is to pro vide a device as stated, which will be strong and durable, o1 comparatively simple con struction, hence of low cost to manufacture.

Other objects will appear hereinafter.

With these objects in view my invention consists in a pair oi pincers of novel construction adapted to grip the farther end portion of a flexible bond of certain construction.

My invention further consists in a lever in which said pincers are pivotally mounted. One end portion of said lever being, when using the tool, adapted to engage a projection or stop provided upon the opposite end portion of said bond, said stop acting as a fulcrum for said lever, such tool being adapt ed, when force is applied to the opposite end portion of said lever thereof, to draw the bond tightly around the for n.

My invention further consists in certain details of construction and arrangement 01' partsall as will be hereinalfter l'ully described and particularly pointed out in the claims.

My invention will be more readily understood by reference to the accompanying drawings forming a part oi this specification, and in which- Figure 1 is a top elevation of a portion olf a form provided with a bond 01 a construction best adapted to be employed in conjunction with my tool, the application of the latte: being herein illustrated. Fig. 2 is a top plan. view 01' my tool in its preferred form, a portion of the lever being broken away so to better illustrate the construction 01' the pincers. Fig. 3 is a side elevation thereof, a

portion 01' the pincers being broken away, and Fig. 4 is a detail of the jaw portion 01' the pincers.

Referring now to the drawings 1 indicates a pair of pincers composed ol the ttllElS 22, the same being identical in construction and pivotally connected at 3. Said arms are so formed that by depressing the handle portions 44 01 the arms 2-2 respectively together causes the jaws 55 thereof to open, for a purpose which will be hereinafter described. A leal' spring 6 having its end portion 7 secured to the arm 2, as by rivets 7, normally hold the jaws 55 in closed posi* tion.

8 indicates a lever arm, the same being 01' any suitable length. The one end portion 01' said lever is formed into a handle piece or grip S, the opposite end portion thereof being provided with a longitudinally extending slot 9, in which slot is substantially centrally positioned and pivotally secure said pincers 1. Said pivotal connection is formed by links 10 constituting toggle levers, the inner end portions 01' which are pivotally secured, the same resting between bosses 11 formed upon and inwardly projecting from the sides oi"said slot, by means of a pivotal pin 12, the outer end portions of said links being pivotally secured to the arms 01' said pincers by means of pivotal pins 13 passing through pairs of ears 14 provided upon. said arms, between which the outer end portions of said links rest, as clearly shown in Fig. 2.

In Fig. 1 is shown the form of bond to which my device is best applicable. The exact and detail construction 01 said bond being described and specifically claimed in a coincident-1y filed application, it is not deemed necessary to here so fully describe the same, enough description being, however, given to familiarize one with the operation thereof. lVith this in view said bond consists in a generally metal band 15 to the end portion 16 of which is fixedly secured a member 17. The forward end portion of said member 17 is formed into ears 18 between which is pivotally secured the cam formed portion of a cam lever 19, adapted when in closed position, to securely grip or hold between itself and the member 17 the end portion 20 of the band 15. The extremity 21 01' the member 17 is grooved,as shown in Fig. 1, in which groove is adapted to rest, when using the de vice, the flanged end portion 22 of the lever 8 thereof. By depressing the handle portions erases 4-4of the pincers 1, the jaws thereof, which versely therethrough, substantially as deare of extraordinary width, may be opened and positioned so as to grasp the end portion 20 of the bond band, the contacting surface of said jaws being preferably grooved or roughened for obvious reasons. Now, by applying force tothe handle portion 9 of the lever 8, it is obvious that the bond may be readily drawn tightly around the form, all possibility of slippage of the pincer j aws upon the surface of the bond band being obviated,

as it is evident that by the provision of the links 10, the greater the pressure or force applied to the lever, the more firmly will the pincer jaws be forced into contact with said band. The firmness of the band around the form is limited by the force applied to the lever of the device. By lengthening the handle portion of the lever, the utility of leverage of the lever thereof may be increased, in which event only a small amount of force need be applied to cause the firm binding of a .bond around a form.

By the provision of a tool of a construction as described, form bonds of a character as stated may be readily and effectually applied to the forms.

While I have shown what i deem to be the i l preferable form of my tool, I do not wish to limited thereto, as there might be many changes made in the details of construction and arrangement of parts without departing -from the spirit of my invention. And al though I have designed my tool with said reference to the application of bonds to forms for concrete construction, I may use the same in any other connection to which it is applicable.

Having described my invention what I claim as new and desire to secure by Letters Patent is: V

1. In a device of the class described, a le- .iver having a slot therein, pincers pivotally "secured in sand slot and extendlng transscribed.

2. In a device of the class described, a lever, pincers in pivotal comiection with one end portion of said lever adapted to grip said band, said pivotal connection consisting of a pair of links, corresponding end portions of each of said pair being respectively in pivotal connection with said lever and the arms of said incers, substantially as described.

3. n a device of the class described, a

slotted lever, pincers pivotally secured in theslot in said lever, said pivotal connection consisting of a pair of links, corresponding end portions of each of said pair being respectively in pivotal connection with said lever and the arms of said pincers, said links being so arranged that when force is applied to one end of said lever, the opposite eX- tremity thereof being fulcrumed, the jaws of said pincers will be forced together, substantially as described.

4. In a device of the class described, a

slotted lever, pincers pivotally secured in the slot in said lever, said pivotal connection consisting of a pair of links, corresponding end portions of each of said pair being respectively in pivotal connection with said lever and the arms of said pincers, said links being so arranged that when force is applied to one end of said lever, the opposite extremity thereof being fulcrumed, the jaws of said pincers will be forced together, and spring means normally holding the jaws of said pincers in closed position, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

oriARL rs M. MARKHAM.

lVitnesses HELEN F. LiLLis, JANET E. HOGAN. 

